Prescriptive corrugated dovetail anchor/ties normally used to secure masonry veneer to concrete backing or masonry walls to concrete structural members shall have the following characteristics:
(a) thickness: 1.52 ±0.15 mm;
(b) width: 25 ±2 mm;
(c) minimum width at neck of dovetail: 13 mm;
(d) length of dovetail end: 25 mm;
(e) wave length of corrugation: 10 ± 1 mm;
(f) depth of corrugations from crest to trough: 2 to 3 mm; and
(g) corrugations extending along at least the length of that part of the tie covered in mortar.
Prescriptive corrugated dovetail anchor/ties used as ties shall have a maximum design width of cavity of 40 mm and conform to one of the following maximum spacing combinations:
(a) 725 mm horizontal, 400 mm vertical; or
(b) 475 mm horizontal, 600 mm vertical.
10.6.1 Bar anchors
Note: See Figures B.16 and B.17
Prescriptive bar anchors normally used to connect masonry walls to other masonry wails or to structural members shall have the following characteristics:
(a) width: 38 ± 2 mm;
(b) thickness: 4.76 ± 0.2 mm; and
(c) hooks that are turned up or turned down a minimum of 50 mm at each end of the bar, or an equivalent mechanical anchorage device.
When prescriptive bar anchors are placed into the mortar joints of a masonry wall that is perpendicular to the bar, the minimum depth of embedment shall be 100 mm.
When prescriptive bar anchors are placed in the mortar joint of a masonry wall that is parallel to the bar, the minimum depth of embedment shall be 450 mm.
When prescriptive bar anchors are embedded placedjn cells of hollow or semi-solid masonry units, such cells shall be filled solid with mortar or grout for a depth of 200 mm above and below each embedded anchor.
Where prescriptive bar anchors are connected to supporting steel or concrete, such connections shall be capable of developing at least 50% of the strength of the steel cross-section in tension.
Anchors not only connect masonry walls to other walls and to structures, but are also used to connect structures to masonry walls. For example, a rod anchor securing a roof deck to a wall (see Figures B.21 and B.22. Figures B. 19 and BrgQ) performs the following functions:
(a) it resists wind uplift on the roof deck;
(b) it provides lateral support to the top of the wall and resists wind and seismic forces acting normal to the wall; and
(c) it resists the diaphragm loads in the roof deck that act parallel to the wall.
It is conceivable that all three of these forces could act simultaneously. Anchors should be carefully selected to resist all of the forces to which they can be subjected. On the other hand, it is sometimes desirable to select an anchor that flexes, hinges, or slides in one or more directions to avoid attracting loads resulting from the deflection of structural members or other differential movements between wall and structure.
A.2. 1 – PRESCRIPTIVE ANCHORS
The following fist describes the different prescriptive anchors:
(a) Prescriptive dovetail anchors and prescriptive corrugated dovetail anchors (see Figures B.8): these anchor/ties can be used to anchor masonry walls to concrete structural members. Full vertical adjustment is obtained with these types. The dovetail slot derives most of its strength from its embedment in concrete and should not be surface mounted.
Note: See Clause A. TJ_.2(4b) for a discussion of the dovetail slot.
When one of these connectors is used to anchor masonry walls to concrete structural members, it is required to transfer loads from the masonry to the concrete by axiai tension, axial compression, or shear, depending on its orientation with respect to the plane of the masonry wall and the direction of loading on the wall. These connectors may also be used when the direction of loading in the connector is other than axial, provided that all components are designed or tested for each application.
(b) Prescriptive bar, prescriptive bolt, and rod anchors (see PJQures-&f&-B.1 0, and B.I 6 te-BrSOFiqures 8,16 to B.22): these anchors are used to connect masonry walls to other masonry walls or to structural members. If there is sufficient space between the masonry and the structural members (see Figure B.16Figure B.19), this type of anchor can flex sufficiently in one or more directions to permit some differential movement, or it can be made fully adjustable, as shown in Figure B.4 Bar anchors made from plate not thicker than 4.76 mm can usually be accommodated in mortar joints.
Thicker anchors should be embedded in mortar in special recesses.
A.1.1.2 ANCHORS (OTHER THAN PRESCRIPTIVE ANCHORS)
A. 3. 22. 3-1. 2. 2.1 Anchors for Walls
The following list describes some anchors commonly used in masonry construction that are not prescriptive anchors under this Standard:
(a) Partition anchors (see Ptgyre B. ^Figure B.S3) : these anchors are used to laterally restrain the tops of partitions. A space should be left above the top of the partition where the structure above is likely to deflect under service loads.
(b) Rigid shear anchors (not illustrated in Annex B): these anchors are used to develop the calculated shear on the vertical plane between two intersecting shear walls. The capacity of this type of anchor depends on a complex interaction of bending, shear, and the crushing strength of the masonry, and should be evaluated by testing or through engineering analysis.
(c) Shear-friction anchors (not illustrated in Annex B): these anchors are used to develop the calculated shear on the vertical plane between two intersecting shear walls. Unlike the rigid shear anchor described above, this type of anchor acts as a tensile member between the walls to keep them tightly joined.